Antibiotic susceptibility and serotypes of Streptococcus pneumoniae isolates from Hungary

Objective: Hungary has reported one of the highest incidences of penicillin resistance in Streptococcus pneumoniae in Europe since the 1970s and is still cited accordingly. However, since the end of the 1990s the resistance of pneumococci in Hungary has not been investigated. In this study we assessed the current situation, particularly to establish whether the incidence of resistance is increasing and if this could be related to the spread of specific strain types. Methods: Isolates of S. pneumoniae (n = 304) were collected by five diagnostic laboratories in Hungary in 2000-2002. Their identity was confirmed and their susceptibilities to 16 antibiotics were determined by the agar dilution method according to NCCLS guidelines. Representative strains were serotyped (n= 112). Results and conclusions: We found significantly lower resistance rates for penicillin compared with the data previously reported from Hungary, but the intermediate resistance was high, at 37%. Macrolide resistance was a bigger problem (similar to40% for erythromycin), although there was full susceptibility to telithromycin. The strains with the highest MICs were isolated from carriers and young children. The fluoroquinolones were very effective, especially moxifloxacin and gatifloxacin. There was full susceptibility to vancomycin and linezolid. We found inconsistencies with previous reports in the survey of the resistance and identification of S. pneumoniae in the country. The serotype distribution of the isolates showed a much greater diversity than had previously been reported; however, there was correlation between serotype and resistance.